Database Technology

Mark Wong is progressing on the PostgreSQL Performance Farm initiative by leveraging AWS Open Source Credits through Kiro Powers. This funding enables large-scale OLTP testing, specifically to update legacy DBT-5 test kits developed during the OSDL era. The effort involves collaboration with AWS maintainers to validate PostgreSQL performance on EC2.

• AWS credits via Kiro Powers are funding the PostgreSQL Performance Farm project.
• Legacy DBT-5 OLTP test kits need updating for modern cloud environments.
• Testing focuses on large-scale OLTP workloads on EC2 instances.
• Collaboration with AWS and maintainers is accelerating the initiative.

A performance benchmark comparing memory allocators in Percona Server for MySQL revealed unexpected memory usage patterns specifically tied to stored procedures. The investigation highlights how routine database setup decisions can lead to surprising resource consumption during execution. These findings suggest that memory allocation strategies significantly impact the overhead of stored procedural logic.

• Unexpected memory spikes occur during stored procedure execution in Percona Server.
• Memory allocator choice directly influences the baseline overhead of procedural logic.
• Benchmarking reveals hidden costs often missed during standard operational monitoring.
• Review memory allocation settings if stored procedures are heavily utilized.

PostgreSQL 19 introduces native support for SQL Property Graph Queries (SQL/PGQ) per the ISO/IEC 9075-16:2023 standard. The update includes the GRAPH_TABLE table function for pattern matching and new DDL commands to manage property graphs. These changes are backed by new system catalogs and information schema views to facilitate graph operations directly within SQL.

• Native graph pattern matching via GRAPH_TABLE eliminates external tool dependency
• ISO/IEC 9075-16:2023 compliance ensures standard SQL graph query syntax
• New DDL commands simplify property graph lifecycle management
• System catalogs provide visibility into graph metadata and structure

PostgreSQL 18 introduces a new Grand Unified Configuration parameter allowing extension control and SQL files to reside outside the server's core directories. This change enables operators to mount extensions as independent OCI container images at runtime, eliminating the need to rebuild the base PostgreSQL image for updates. While this supports leaner fleet management, the decoupling is only effective for extensions that do not rely on deep integration with the server binary.

• PostgreSQL 18 adds a GUC to store extension files outside server directories.
• Extensions can now be packaged as separate OCI images and mounted at runtime.
• Reduces base image size by keeping PostgreSQL unmodified and lean.
• Independent versioning allows rapid updates like pgvector without server rebuilds.
• Decoupling benefits depend on extension depth; tightly coupled extensions gain little.

vip-manager v5 introduces breaking changes that alter cluster behavior during failovers, making pre-upgrade review essential. The tool manages a Virtual IP by monitoring the Distributed Configuration Store for leader elections, attaching the VIP to the current primary. This release requires careful attention to ensure high availability setups do not behave unexpectedly during maintenance windows.

• Review breaking changes before running apt upgrade to avoid unexpected 03:00 failures.
• vip-manager v5 changes how the cluster behaves when leadership transitions occur.
• The tool continues to manage VIPs by watching the DCS for leader info changes.
• Plan your rollout strategy to mitigate risks associated with the new behavior.
• Do not treat this as a simple set-and-forget tooling update.